General concepts

Day Master

Also known as: daymasterday master baziri zhuri yuan日主日元day stemday master elementself elementbazi day masterilgannikkan

The Day Master (Ri Zhu, 日主) is the Heavenly Stem of the day pillar in a BaZi chart. The tradition treats it as the person themself and reads every other sign of the chart in relation to it.

In the earliest forms of Chinese fate calculation the year was the centre of the reading. Xu Ziping, in the Song dynasty, moved that centre to the stem of the day, and the classical method has kept it there ever since. The stem is called Ri Zhu, "master of the day", or Ri Yuan, "origin of the day". It sits on top of the day pillar, above the day branch, which the tradition calls the palace of the spouse. Because day pillars follow an unbroken cycle of sixty days, the Day Master changes from one day to the next and has nothing to do with the month or the zodiac animal of the year.

There are ten possible Day Masters: the five phases, each in a yang and a yin form. The tradition gives each of them an image from nature. Jia (甲), Yang Wood, is a tall tree: growth, a straight direction and steadiness. Yi (乙), Yin Wood, is grass, a flower or a climbing plant: flexibility and finding a way around obstacles. Bing (丙), Yang Fire, is the Sun: warmth, openness and being seen. Ding (丁), Yin Fire, is a candle or a lamp: focused warmth and attentiveness. Wu (戊), Yang Earth, is a mountain: stability and reliability. Ji (己), Yin Earth, is fertile field soil: care, practicality and helping things grow.

Geng (庚), Yang Metal, is raw ore, an axe or a sword: decisiveness and directness. Xin (辛), Yin Metal, is a jewel or a fine blade: precision and refinement. Ren (壬), Yang Water, is the sea or a great river: breadth and movement. Gui (癸), Yin Water, is rain, dew or mist: subtlety and quiet influence.

These images are a starting point, not a portrait. The tradition never reads a Day Master alone. A Jia born in spring, the season of Wood, is described differently from a Jia born in autumn, when Metal rules. Practitioners look at the month branch, at roots of the same phase among the hidden stems, at the stems that support the Day Master and at those that drain or control it. From that balance many schools judge whether the Day Master is strong or weak and which phase would balance the chart, the useful phase called Yong Shen. The schools weigh these factors differently, so two practitioners can describe the same chart in different terms.

The Day Master is sometimes compared to the Sun sign of Western astrology, since both are the usual first step into a chart. They are calculated very differently. The Sun sign depends on the time of year, while the Day Master depends on the exact date in the sixty-day cycle. For a birth between 23:00 and midnight schools also disagree on whether the day pillar already belongs to the next day.

The free BaZi calculator in AstroSensus shows the Day Master with its phase, its polarity and its traditional image, and gives every other stem its Ten God in relation to it. It does not assess whether the Day Master is strong or weak. Like the rest of BaZi, the Day Master is a symbol for reflection, not a verdict about who someone is.